With the rapid development of the Internet and the popularization of the mobile phone with the large screen and multiple functions, a large quantity of mobile data multimedia services and various broad bandwidth multimedia services occur, such as the video conference, television broadcast, video on demand, advertisement, online education, and interactive game and so on, which not only satisfies the continuously increased service demand of the mobile user, but also brings new service increasing points for mobile operators at the same time. These mobile data multimedia services need that a plurality of users are able to receive the same data at the same time, and comparing with the common data service, these mobile data multimedia services have features of large data quantity, long duration, and sensitive time delay and so on.
In order to effectively utilize the mobile network resources, the 3rd Generation Partnership Project (3GPP) proposes the Multimedia Broadcast Multicast Service (MBMS), and this service is a technique of transmitting data from one data source to a plurality of destinations, which implements to share the network (including the core network and the access network) resources, and improves the utilization ratio of the network resources (especially the air interface resources). The MBMS defined by the 3GPP is not only able to implement the pure text and low speed message classified multicast and broadcast, but also able to implement the multicast and broadcast of the high speed multimedia service, and provide various rich video, audio and multimedia services, which undoubtedly complies with the trend of the development of the future mobile data, and provides a better service prospect for the development of the 3G.
In the LTE, the MBMS service can adopt a way of the multicast mode, which is called as the Multicast/Broadcast over Single Frequency Network (MBSFN) sending mode, and the MBMS service sent by adopting the multicast mode is also called as the MBSFN service, which is able to adopt the same modulation and coding format in a plurality of cells, and adopt the same physical resources to send the same content, and the features of the MBMS cell transmission are as follows:
1) synchronization transmission in the MBSFN area; 2) the MBMS transmission combination of multiple cells is supported; 3) the Multicast Traffic Channel (MTCH) and the Multicast Control Channel (MCCH) are mapped into the Multicast Channel (MCH) in the point to multipoint (p-T-m) mode; 4) the MBSFN synchronization area, MBSFN area, MBSFN transmission, advertisement, and reserved cell are all maintained in the semi-static configuration by operations.
Thus, User Equipment (UE) of a plurality of cells can receive a plurality of MBMS data with the same content and carry out the Single Frequent Network (SFN) combination, thereby being able to improve the gain of the receiving signal. A plurality of cells adopting the same physical resources and sending the same MBMS service in the MBSFN sending mode composes one MBSFN area.
In the practical LTE networking, one MBSFN area has a plurality MBSFN services, and all the MBSFN services belonging to one MBSFN area are called as one MBSFN service group, and that is to say one MBSFN service group only belonging to one MBSFN area. One MBSFN area comprises a plurality of cells, and each cell is configured with one completely same MBSFN service group. The data channel MTCH of a plurality of MBSFN services with the same MBSFN area and the control channel MCCH of the MBSFN services can be multiplexed to one Multicast Channel (MCH). The MCCH and a plurality of MTCHs of the same MBSFN area namely a plurality of logic channels can be mapped into the same one transmission channel MCH.
In the LTE system, the MCH is a transmission channel, of which the feature is that point to multipoint transmission is carried out, and the corresponding physical resources are the multicast resources allocated by the system for transmitting the MBMS services (MTCH), and one MCH is born on a plurality of multicast resources, and these multicast resources comprise a plurality of MBSFN frames and MBSFN subframes, as shown in FIG. 1,  denotes the non MBSFN frame,  denotes the MBSFN frame,  denotes the non MBSFN subframe,  denotes the MBSFN subframe, and  denotes the fixedly unavailable. These multicast resources adopt a suit of MBSFN subframe allocation patterns (MSAP) to be configured, including the radio frame allocation pattern and the radio subframe allocation pattern, and the multicast resources of each MBSFN area can be divided into a plurality of groups taking the subframe as an unit according to a certain pattern, and each group can compose one MCH or a plurality of groups composes one MCH. Then the used pattern composing each MCH is called as the MSAP of this MCH, and one MSAP describes the physical resources of one MCH channel. Each cell can have one or more MCHs, and each MCH uniquely corresponds to one MSAP, and uniquely belongs to one MBSFN area, however, each MBSFN area can have one or more MCHs, and the method for configuring the multicast resources configured by each MCH is to configure one suit of MSAP for each MCH.
As shown in FIG. 2, in order to improve the sending efficiency of the MTCH, a plurality of MTCHs born on each MCH can adopt the dynamic scheduling method, and 2 or more than 2 MTCHs can be multiplexed on the same MBSFN subframe and occupy part of resources of this subframe by the dynamic scheduling, and FIG. 2(a), FIG. 2(b) and FIG. 2(c) are the schematic diagrams of the resource allocation of the Scheduling Period 1, Scheduling Period 2, and Scheduling Period 3 respectively. In the public prior art, the MSAP occasion is introduced into the MSAP concept at the same time, which indicates all the multicast resources included in one MCH corresponding to a certain MSAP in the time period of one scheduling period (namely a time period on the radio interface, a plurality of services are sent on the MBSFN subframe scheduling resources included in the scheduling period according to an order in sequence). A plurality of MTCHs and the Dynamic Scheduling Information (DSI, which is also briefly called as scheduling information in the present invention) of these MTCHs can be sent in one MSAP occasion. The dynamic scheduling information refers to the information of the specific location information of the service in the scheduling period, and the dynamic scheduling information can be sent in the scheduling period, or sent in the previous one or more scheduling periods of the scheduling period, and generally the scheduling information should be sent to the UE before sending the service data and the MCCH in the scheduling period indicated by the scheduling information, and the scheduling information can be born on the Medium Access Control (MAC) control element. The length of the MSAP occasion is generally fixed to 320 ms. Similarly, one scheduling period is generally fixed to 320 ms, and also can be 2n×320 ms (n=−3, −2, −1, 0, 1, 2, 3, 4, . . . , N), accordingly, the time length of the MSAP occasion is 40 ms, 80 ms, 160 ms, 320 ms, 640 ms, and 1280 ms and so on, and the time length of one MSAP occasion is one scheduling period, and also can be called as one scheduling period. One or more MBSFN subframes in one or more MBSFN frames are allocated to one MCH through the MSAP, wherein the subframe sent by adopting the multicast mode is called as the MBSFN subframe, and the frame including the MBSFN subframe is called as the MBSFN frame. One MBSFN area has a plurality of MCHs, and each MCH has its own scheduling period, which is also called as the MSAP occasion, and the scheduling periods of different MCHs can be the same or can also be different.
In the prior art, each MCH has one schedule block bearing its dynamic scheduling information (DSI) as shown in FIG. 2, and generally the DSI is born on the MAC Service Data Unit (SDU), and is configured before its scheduled MCH, as shown in FIG. 3.
Each MSAP occasion configured for one MCH bears the scheduling information, including the mapping information from the MTCH to the MSAP subframe, and this type of mapping information is determined by means of the index relationship of the MBSFN subframe number in one scheduling period, and UE can know which MBSFN subframes each MTCH is allocated to by reading scheduling information. UE can read its interested MTCH on the corresponding MBSFN subframes, and ignore the MBSFN subframes which do not require reading, thereby improving the MBMS service receiving efficiency of the UE, and saving the power consumption of the UE. Herein said MBSFN subframe number is determined in this way: ordering all the MBSFN subframes allocated in one scheduling period by one MCH according to an order, and numbering all the MBSFN subframes in sequence. For example, the total number of the MBSFN subframes allocated in one period by a MCH channel is 100, and then the subframe numbers are from 0 to 99 or from 1 to 100.
In the existing LTE technique, a plurality of transmission channels multiplex the MCH channel in a following way: one subframe corresponding to one Transmission Time Interval (TTI), one output data block being able to be sent in one TTI, and corresponding to one Media Access Control Protocol Data Unit (MAC PDU). One MAC PDU can include a plurality of MAC SDUs and MAC control elements (MAC CEs), and these MAC SDUs can come from different logic channels, and possible logic channels include the MTCH, MCCH, and MSCH and so on, and the MAC CE can bear dynamic scheduling information. These data from different logic channels are concatenated together and then are sent together in the physical channel. In order to differentiate the MAC SDUs from the different logic channels, the MAC PDU includes the identification information, and specifically includes the identifier of the logic channel, and the location information of the data block of this logic channel in the MAC PDU and so on, which is used for the receiving end differentiating the data blocks of different logic channels.
Since the areas of transmitting the MBMS service are different, a plurality of MCHs are likely to exist in a certain cell, and respectively bears the services belonging to different MBMS service areas; besides, since the Quality of Service (QoS) attributes of services are different, one MBSFN area is also likely to be configured with a plurality of MCHs, and each MCH respectively is configured with the different Modulation Coding Schemes (MCS), and respectively bears the MBMS service with different QoS requirement, and also includes the MCCH and DSI with the special QoS requirement. In a scenario of a plurality of MCHs existing, how to send the scheduling information and select the corresponding MCS requires designing.